ORNITOLOGIA NEOTROPICAL 16: – , 2005
© The Neotropical Ornithological Society
STRATEGIES FOR THE CONSERVATION MONITORING OF
RESIDENT LANDBIRDS AND WINTERING NEOTROPICAL
MIGRANTS IN THE AMERICAS
Steven C. Latta1,3, C. John Ralph2, & Geoffrey R. Geupel1
1
PRBO Conservation Science, 4990 Shoreline Highway 1, Stinson Beach, California 94970,
USA.
2
U.S. Forest Service Redwood Sciences Laboratory, 1700 Bayview Dr., Arcata, Caifornia
95521, USA.
Resumen. – Estrategias para el monitoreo y conservación de aves terrestres residentes y migratorias
neotropicales en las Américas. – Muchas organizaciones a nivel internacional, regional y local, han concordado con la necesidad de establecer programas de monitoreo de aves a largo plazo en las Américas. Sin
embargo, el reto de desarrollar programas de monitoreo nacional e internacional es difícil, debido a la falta
de biólogos capacitados u otros recursos en las regiones claves. Más aún, aquellas organizaciones locales
que cuentan con personal y recursos para desarrollar un programa de monitoreo, usualmente tienen sus
propias metas y objetivos de monitoreo definidos a nivel local. Estos objetivos pueden variar entre regiones y países, pero deben apoyarse durante el diseño y financiamiento de programas de monitoreo a gran
escala. Presentamos una estrategia de monitoreo que permite a las organizaciones locales generar resultados de importancia para sus esfuerzos de gestión local, y que al mismo tiempo les permite participar en
esfuerzos de monitoreo más amplios, a nivel regional e internacional. Bajo esta estrategia, los resultados de
esfuerzos conjuntos sirven a su vez para determinar las tendencias poblacionales y las relaciones de hábitat
de las aves migratorias y residentes, a una escala mucho mayor que la que puede ser alcanzada por un
esfuerzo de monitoreo aislado. Igualmente, esta estrategia nos permite enfocarnos en resolver preguntas
básicas sobre la ecología y la historia natural de las especies de aves migratorias y residentes. A través de un
esfuerzo cooperativo como el presentado aquí, y mediante el uso de protocolos que incorporan métodos
de monitoreo estandarizados, podemos evaluar la eficacia de las acciones de conservación y manejo a lo
largo de las Américas, y al mismo tiempo cumplir con los objetivos de conservación y monitoreo definidos
a nivel local.
Abstract. – Many international, regional, and local partner organizations have agreed in the need to establish long-term bird monitoring and research programs in the Americas. However, the challenge of developing national or international monitoring programs is difficult often because of the lack of qualified
biologists or other resources in key regions. More fundamentally, locally-based organizations that may have
personnel and resources that could be involved in monitoring programs often have their own goals and
locally defined monitoring objectives. These objectives may vary among regions and countries, but must be
supported when designing and funding monitoring programs. Here we present a monitoring strategy that
allows locally-based organizations to generate results that will have relevance to their local management
efforts, while enabling them to participate in wider, regional and international monitoring efforts that will
______________
3
Corresponding author e-mail: slatta@prbo.org
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LATTA ET AL.
help to determine population trends and habitat relationships of both migratory and permanent resident
birds, at a scale far greater than any single monitoring effort. It also allows to address basic research questions of the ecology and natural history of migratory and resident bird species. Through a cooperative
effort such as outlined here, and with the use of protocols that incorporate standardized monitoring methods, we can evaluate the efficacy of conservation and management actions throughout the Americas, while
also fulfilling locally-defined conservation and monitoring objectives. Accepted 3 March 2005.
Key words: Monitoring, Latin America, Neotropical migratory birds, avian ecology, avian conservation.
INTRODUCTION
The conservation and management of terrestrial landbirds requires the collection of habitat-specific data on population parameters
because a vast majority of conservation and
management activities are related to the population size of a species (Faaborg 2000). For
example, population dynamics of game species must be understood well enough to allow
continued harvest activities without negative
impacts on future reproduction and population levels. With threatened and endangered
species, we must know the distribution of
species, the population size, population trend,
and primary population parameters in order
to develop and evaluate effective conservation plans. For species that are neither harvested,
threatened,
or
endangered,
monitoring activities must be adequate to
detect population trends so that declining
species can be recognized while they are still
relatively abundant. Linking bird population
data to specific habitat types, land-use practices, or landscapes is perhaps the most effective way to allow managers to use the
information effectively in setting conservation priorities and assessing the effect of management actions (Martin 1995, Hutto &
Young 2002).
Many international, regional, and local
conservation organizations have agreed to the
need to establish long-term avian monitoring
and research programs in the Americas. Much
discussion over the past decade about the
establishment of bird monitoring programs
2
throughout the Americas has established the
need for the use of standardized methods in
monitoring bird populations (e.g., Ralph &
Milá 1994, Geupel & Warkentin 1995, Latta et
al. 2003). Data on population parameters
must be quantifiable and collected in a similar
manner on a regular basis so that comparisons can be made across space and time (e.g.,
Koskimies & Vaisanen 1991). Standardized
monitoring methods for landbirds have been
presented in Ralph et al. (1993, 1996) and are
in general use, but challenges remain in developing national or international monitoring
programs. These challenges include the
potential lack of qualified biologists, methods
of integrated data management and dissemination, and (perhaps more often) the lack of
key resources such as funding. More fundamentally, locally-based organizations that may
have personnel and resources for monitoring
programs often have their own goals and
locally-defined monitoring objectives. These
objectives may vary among regions and countries, but must be supported when designing
and funding monitoring programs.
Here we present a monitoring strategy
that allows locally-based organizations to generate objectives and results that will have relevance to their locally-defined management
efforts, while enabling their participation in
wider regional and international monitoring
efforts that will help determine population
trends and habitat relationships of migratory
and permanent residents birds at a scale far
greater than any single monitoring effort. It
also allows us to address important (and often
CONSERVATION MONITORING OF LANDBIRDS
TABLE 1. A strategy for the conservation monitoring of landbirds in the Americas based on six levels of
monitoring. Increasing the level of monitoring (from level A through level F) increases complexity and
cost, but builds the level of knowledge needed for effective conservation. The key questions and techniques from lower levels of monitoring which may still be addressed are included in higher levels also.
Basic questions
CENSUS METHODS
Monitoring objectives
Basid technique(s)
Level A: Species presence/absence
What species are present?
Observations
Level B: Population size
How large is the population?
Where are the birds (and why)?
What species are present?
Single set of counts
Habitat measurements
Observations
Level C: Population trends
What is the population trend?
How large is the population?
Where are the birds (and why)?
What species are present?
Repeated sets of counts
Habitat measurements
Observations
Level D: Ecology/natural history
What are birds doing (and when)?
What is the population trend?
Where are the birds (and why)?
What species are present?
Constant-effort mistnetting
Repeated sets of counts
Habitat measurements
Observations
DEMOGRAPHIC METHODS
Level E: Reproductive success
What are the causes of population
changes
What is the reproductive rate?
What is the population trend?
What are the birds doing (and
when)?
Where are the birds (and why)?
What species are present?
Monitoring of nests
Habitat measurements
Observations
Level F: Survival and productivity
What are the causes of population
change?
What are the rates of productivity
and survival?
What is the population trend?
What are the birds doing (and
when)?
Where are the birds (and why)?
What species are present?
Constant-effort mistnetting
Color-band resighting
Repeated sets of counts
Habitat measurements
Observations
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LATTA ET AL.
novel) basic research questions of the ecology
and natural history of migratory and resident
bird species. Through a cooperative effort
such as outlined here, and with the use of
protocols that incorporate standardized monitoring methods, we can evaluate the efficacy
of conservation and management actions
throughout the Americas, while also fulfilling
locally-defined conservation and monitoring
objectives.
In building a candidate monitoring
scheme, we suggest six conditions to strive
for achieving. First, the proposed monitoring
strategy should focus on methods that are
intended to apply over a relatively small spatial scale, such as a refuge, national park, or
forest preserve of perhaps 10,000 km2 or less,
where management actions need to be based
on information from the local area. Within
each area, one or more monitoring sites could
be established incorporating the methods
described here. Second, we propose that all
methods should be, to the greatest extent
possible, mutually compatible, so that existing
programs at a station can, with minimal perturbation, be integrated with other existing or
proposed programs at other stations. Third,
monitoring efforts should seek to understand
factors that involve both Neotropical migratory birds and permanent resident species. To
implement this condition, one would conduct
surveys both during the northern winter
when Neotropical migrants are present, and
during the season when most permanent resident species are breeding. Fourth, we emphasize the need for basic research into the
ecology and natural history of both resident
and migratory birds. As the Partners in Flight
Research Working Group (2002) has pointed
out, monitoring, research, and management
are closely interrelated, and much research
depends on well-coordinated monitoring
efforts; clearly the mechanisms of population
change can best be understood through continued and expanded population monitoring.
4
Fifth, monitoring efforts should strive to seek
to understand both primary and secondary
population parameters whenever possible, as
it is important that we identify not only negative population trends, but also the demographic factors that might be associated with
population declines. And finally, the data at
any monitoring station should be able to be
upwardly integrated. No matter what the
resources of the operator at a station, the data
are much more valuable if they contribute to
larger programs. Specifically, an operator can
contribute to one or more monitoring objectives for a single site, and further, those data
can also be aggregated to answer larger,
regional questions.
A MONITORING STRATEGY IN SIX
LEVELS
We suggest that the general goals of any bird
monitoring program can usually be placed
among six objectives and their concomitant
methods, and these can be arranged semi-linearly in an interactive structure from ëLevel A
monitoringí to ëLevel F monitoringí such that
each can form the foundation for the next
level (Table 1). As we envision this sequence
of objectives, as one moves from level A
through level F, one gains additional knowledge concerning avian populations and ecology, the complexity of monitoring methods
increases, and costs and personnel needs for
the monitoring program increase.
At its simplest, avian monitoring consists
of an inventory, that is, the determination of
presence or absence of various species (Level
A). Building on this foundation, we can construct successively more complex objectives,
including: defining population size, and determining habitat relationships based on a
broad-scale set of point counts (Level B); estimation of long-term population trends with
censuses based on repeated counts (Level C);
determining the population ecology and life
CONSERVATION MONITORING OF LANDBIRDS
history of species through constant mist-netting effort or observations (Level D); the
determination of reproductive success and
reproductive rate through nest monitoring
(Level E); and, the estimation of population
composition and limitations through demographic parameters, such as survivorship and
site fidelity, with a comprehensive program of
mist netting and/or color-band resighting
(Level F). With each new level, methods are
added, or their intensity is increased, and at
the same time understanding and perspective
are increased. Below we define more clearly
these monitoring levels.
Level A monitoring: Species presence or absence
through observation. This level of monitoring is
an inventory, and is the basic level of monitoring. Techniques include various counting
methods, area searches, targeted searching,
and the compilation of data from historic
records, birdwatchers, and others familiar
with the area. This would result in a checklist
of birds over time, such as many protected
areas and parks have already accomplished.
Checklists are usually augmented by subjective estimates of relative abundance of species,
habitat associations, and seasonal changes in
presence and abundance.
Level B monitoring: Estimating population size
through a single set of counts. Monitoring at this
level involves the possibility of evaluation of
many habitats and many species. Estimations
of population size with variable-distance
counts, habitat relationships, and habitat
requirements can be generated with this monitoring method (e.g., Hutto et al. 1986, Lynch
1989). Point counts are usually considered as
the best option during the breeding season,
when species are actively singing, but they
have also been used at all times of the year.
Area search counts (usually 20 min in duration) are also considered a good option during
all times of the year, and are especially useful
for flocking species.
This monitoring method reflects guidelines presented in Ralph et al. (1993, 1995) and
Faaborg (2000), in which a route of many
point counts, or a series of area searches is
recommended. For point counts, we suggest a
minimum of 25 census stations/habitat.
Routes are preferentially located on tertiary
roads, then secondary roads, and then offroad trails. Primary roads should be avoided
to reduce edge effects. Using either a 5-min or
10-min, unlimited-radius point count, we recommend that all birds seen and heard at a station be tallied, both inside and outside a given
distance (for example 25 or 50 m). The distance to each individual bird can also be
recorded so that detection probabilities and
density of birds can be determined rather than
relying on the index of number of birds per
station (Ralph & Scott 1981, Burnham &
Anderson 1984). For area searches, all birds
seen within and outside the observerís walking circle are tallied. We suggest specific seasons for surveys; for example, wintering
Neotropical migrants could be censused
annually during January, or several times during the northern winter, while breeding birds
could be censused at a locally-determined
date.
The advantages of a census are its ability
to detect many species simultaneously, as well
as population-level responses to habitats, and
the relatively easy logistics of implementation.
Its main disadvantages are that roadside habitats will be different in some degree from a
random sample of an area, and observer variability may be somewhat higher than in the
demographic methods described below. This
variability results from the difficulty of learning to identify a large number of species, especially in the diverse tropical forests, and the
seasonality of detection rates. Some of these
disadvantages can be ameliorated by recording the distance to each individual bird as
noted above. Alternatively, it can be advanta5
LATTA ET AL.
geous to select a subset of focal species and/
or easily recognized species to count (Geupel
& Warkentin 1995, Chase & Geupel in press).
In addition to counts, we recommend that
vegetation measurements be made at each
census station to provide on-the-ground
information on habitat characteristics for
developing land management guidelines and
habitat requirements of the species. At a minimum, such data should allow comparison
with remote sensing data or aerial photography. At the ultimate level, it can give fine-scale
resolution of habitat preferences. There are
many suggestions on how to complete vegetation measurements, but the most likely to
prove useful is one that is rapidly taken and
gives an overview of the vegetation, without
great detail. Such a method, the relevé (Ralph
et al. 1993), involves estimating the height of
layers in the vegetation, identifying principal
tree and shrub species or species groups, and
determination of percent cover of each species in each vegetation layer. Most birds
respond to habitat on this fairly large structural and spatial scale (Verner et al. 1986),
rather than on the presence or absence of, for
instance, the small plants in the herb layer.
Level C monitoring: Estimating population trends
with repeated counts. This level of monitoring is
an elaboration of level B monitoring, and
consists of a system of counts repeated at
least annually. While level B monitoring calls
only for a single visit to each counting station,
if such censuses are repeated annually, they
can provide information on population trends
(Nur et al. 1999). This monitoring protocol
(when using 3-min point counts repeated
annually) is similar to that of the North
American Breeding Bird Survey (Robbins et
al. 1986). The intent of the breeding bird survey is the detection of large-scale trends in
population sizes, so that possible causes of
population changes can be investigated with
further monitoring, research, or management
6
actions. The breeding bird survey is thus
designed to give us a first warning of population changes across a broad region. When
counts are repeated at more frequent intervals, such as monthly, bi-monthly, or quarterly, and of longer duration (5 or 10 min or
greater), counts can also contribute to the
knowledge of ecology and seasonal movements of birds. When vegetation and habitat
measures are taken at regular intervals
(approximately every 5 years) at each station,
as in level B monitoring, it can also potentially
provide on-the-ground information on habitat characteristics for developing land management guidelines and habitat requirements
of the species.
Level D monitoring: Ecology and life history through
constant-effort mist netting. This is a fundamental
monitoring method used to determine the
presence of rare and secretive species, breeding and migration phenology, age structure of
the population, and ecology and life history
of species. Constant-effort mist netting may
be used to determine population trends if
repeated annually (e.g., Faaborg et al. 1984,
Dugger et al. 2001), and it can also provide
the foundation for a much fuller understanding of the demographic changes within populations, as well as the potential causes of
trends revealed by, for example, census-monitoring methods (e.g., Lynch & Whigam 1995).
While constant-effort mist netting is sometimes undertaken once a year, monitoring can
be more productive when nets are operated at
more regular intervals, such as daily, weekly,
monthly, or quarterly, in order to give a fuller
picture of bird activity around the year.
Constant-effort mist netting conducted
throughout the year or in the season of interest can greatly enhance our knowledge of the
population ecology and life history strategies
of species. When coupled with behavioral
observations, repeated counts, or nest monitoring, mist netting can be a valuable, proac-
CONSERVATION MONITORING OF LANDBIRDS
tive tool in understanding changes in bird
populations (Nur & Geupel 1993, Silkey et al.
1999), and detailing vital aspects of the ecology and life history of birds. This can include
molt patterns, prevalence and diversity of parasites, food habits (through analysis of droppings), and temporal changes in body
condition. In addition, level D monitoring
can be used to determine migration movements and dispersal patterns of Neotropical
migrants (e.g., Ralph & Hollinger 2003), as
well as seasonal movements of tropical
resident birds. Migration monitoring through
constant-effort mist netting can assess
migratory patterns, flock composition, and
population trends of species during the annual
spring and fall migrations. This might be particularly important in coastal areas and areas
known as migration stopover sites where
birds rest and refuel before continuing on
migration.
Mist nets in level D monitoring are set in
fixed locations that form a circle, a grid pattern, or a single long line. Depending on bird
activity, one might use 10, 24, or even more
nets (usually 12 m x 2.5 m, 30 or 36 mm
mesh) per site. However, it is important that
net numbers and locations at each site are
fixed within a site so that timing and location
are consistent among years and sites. A given
monitoring station may set their own mistnetting schedule with the understanding that
capture rates decline precipitously as nets are
operated continuously over a few days, and
most operations do not generally exceed three
consecutive days in a single site except during
migration when newly-arriving birds are still
prone to net capture. Migration monitoring
stations generally set mist nets in fixed positions that are opened every 1–3 days throughout the migratory period. While longer
periods between net operations can result in
missing major movements (Ralph et al.,
2004a), or obscuring trends (Thomas et al.,
2004), this might be ameliorated by combin-
ing data from a network of stations (Hussell
& Ralph in press, Ralph et al. 2004b). All birds
netted should be banded with a uniquely
numbered aluminum band. In most countries,
the capture and marking of migratory birds
listed under the Migratory Bird Treaty Act
requires a permit from the host country. As in
other monitoring methods, vegetation and
habitat measures should be taken at regular
intervals (approximately every 5 years) at each
station.
Level E monitoring: Reproductive success through nest
monitoring. The monitoring of birds during the
breeding season has as its goal the determination of local reproductive success and estimation of survival rates of resident species (Nur
et al. 2000). A common and straight-forward
method of monitoring reproductive success is
through nest searching and nest monitoring.
The nest-searching protocol is based on the
Breeding Biology Research and Monitoring
Database (BBIRD) program described in
Martin & Geupel (1993), Ralph et al. (1993,
1996), and Martin et al. (1997). Plots for nest
searching may be variable in size, and can be
in any habitat of interest. The plots are systematically searched for nests, and each nest is
checked every 3–4 days to determine if it is
still active (with eggs or young) or if it has
failed. Vegetation measurements are used to
provide information on microhabitat choices
made by nesting birds and for developing
some aspects of land management guidelines,
with vegetation assessed at the plant containing the nest, and in the area surrounding the
nest site. By directly monitoring nest success
on plots, we can also examine rates and consequences of nest parasitism (e.g., by cowbirds), provide badly needed data on life
history traits, clutch size, and other demographic features of species, and provide direct
information on nesting habitat conditions
associated with high success (Martin & Geupel 1993).
7
LATTA ET AL.
Level F monitoring: Survival and productivity
through mist netting. Level F monitoring is an
elaboration of levels B and D monitoring and
seeks to determine the demographic parameters of populations and habitat-specific measures of site fidelity and survival. This local,
intensive monitoring complements broadscale, rapid monitoring (levels B and C) by
helping to explain population trends that the
more rapid monitoring protocols find. In
level F monitoring, constant-effort mist netting provides an index of annual productivity
and information on annual survival. By addition of recapture of banded birds, or the
resighting of color-marked birds, one can
determine site fidelity and site persistence as
an index of survival among or between seasons.
Level F monitoring is based on work on
wintering migrant site fidelity by Holmes et al.
(1989), Wunderle & Latta (2000), and Latta &
Faaborg (2001, 2002), but can be applied to
both resident species and wintering migratory
birds. Since the documentation of continentwide declines in some migratory species
(Robbins et al. 1989), a growing number of
studies focused on the need for habitat specific, demographic and site fidelity data in
assessing habitat preferences of wintering
migratory birds (e.g., Holmes et al. 1989).
Because some species were shown to segregate by sex and age class, abundance data
alone could be a misleading indicator of population size and habitat preference (Van
Horne 1983). Furthermore, abundance cannot be equated with survival, so data on site
fidelity, including overwintering site persistence and annual return rate, would be
required to assess habitat quality. Thus, recent
studies focused on habitat-specific demographies and site fidelity of wintering migrants
(Holmes et al. 1989, Wunderle 1995,
Wunderle & Latta 2000, Marra & Holmes
2001; Latta & Faaborg 2001, 2002), and these
studies have set the standard for studies of
8
overwintering ecology of migrants.
In level F monitoring, constant-effort
mist netting, color-banding, and resighting of
color-banded birds through area searches is
best repeated at intervals throughout the year
or season of interest. Intervals between capture sessions are generally quarterly or bimonthly, with the more frequent option chosen for seasonal studies. After each capture
session, resighting of color-banded birds can
be accomplished by systematically searching
the study site and the immediate area for individual birds, mapping the location of birds on
prepared site maps, and following birds to
help determine their territories or home
ranges. Resighting should continue until
observers are confident that no more colorbanded birds remain unidentified on the plot.
The protocol presented here is similar in
some aspects to the ëMoSI Programí (Monitoreo de Sobrevivencia Invernal) which seeks
“to determine for each species the habitat
characteristics that provide for adequate overwintering survival and good physical condition at the end of the winter season”
(DeSante et al. 2003). But MoSI largely
attempts to assess habitat-specific overwintering survival of migratory landbirds using mist
netting and capture-recapture models alone.
Color-banding and resighting individual birds
is encouraged as “an excellent means for
improving the precision of survival-rate estimates because, with sufficient effort, resighting probabilities can be substantially higher
than recapture probabilities.” However, participants may be discouraged by the perception that resighting is more “labor intensive”,
and by the lack of access to color bands. But
recapture probabilities of wintering migrants
are often very low, and if the number of mist
netting sessions is several per season, then the
labor can approach being as intensive as one
requiring resighting of color-banded birds. In
addition, a protocol involving resighting
color-marked birds has the advantage that
CONSERVATION MONITORING OF LANDBIRDS
both migrants and permanent residents can
be simultaneously studied, data analyses are
straightforward, and perhaps most importantly, data need not be pooled among many
unrelated sites, but rather, data can be analyzed from a small number of sites (for example, a single reserve) because the inclusion of
resighted color-banded birds allows investigators to increase greatly the ability to track
more individuals birds in the population.
Constant-effort mist netting can also be
used as an alternative method of monitoring
reproductive success through constant-effort
mist netting (DeSante et al. 2001), thus building on monitoring levels D and E. Constanteffort mist netting can provide data on reproductive success by determining the number of
young birds relative to the number of adult
birds that are captured. Promoted as the
Monitoring Avian Productivity and Survivorship (MAPS) program (http://www.birdpop.org/), the method depends on a network
of banding stations collaborating across the
breeding range of the same species, and has
been used to explain very broad-scale patterns
of bird productivity (Nott et al. 2002), but has
not been used to determine trends at the level
of a reserve, state, or similar-sized region.
CONCLUSIONS
Prior to initiating any of these monitoring
programs, important decisions must be made
concerning 1) the objective(s) of the monitoring program, 2) the scale of the monitoring
that is possible given likely available resources,
including funding and personnel, 3) the time
of year that monitoring is of interest, and 4)
the frequency of the monitoring. In the case
of monitoring Neotropical migratory birds on
their wintering grounds, the season is welldefined and reasonably consistent. Monitoring of permanent resident species is less circumscribed because breeding of any given
species may occur at any time of the year
depending upon latitude, altitude, and climate,
and in some species, may even occur more
than once per year.
Once implemented, the methods outlined
here will produce much-needed information
on relative abundance, demographics, and
bird-habitat interactions that can be compared among sites and years. Some of these
monitoring methods (e.g., counts and mist
netting) are much less time-consuming than
biologists and managers sometimes think. A
very worthwhile monitoring program could
involve as few as 10 person-days per year by
implementing road-based point counts, area
searches, or a single mist netting session annually. A complete monitoring program for a
reserve could involve as little as 30–40 person-days per year. The implementation of a
long-term landbird monitoring station is
therefore quite affordable. We particularly
advocate the inclusion where possible of
demographic methods (monitoring levels E
and F) which seek to understand both primary and secondary population parameters so
that we can identify not only negative population trends, but also the problems associated
with population declines (Pienkowski 1991).
Finally, a long-term monitoring program
can also serve as a basis for the development
of a much larger and more comprehensive
avian conservation program. We have seen
many cases where the initiation of a monitoring program based on constant-effort mist
netting, censusing, and/or nest searching, can
serve as a facility to train new biologists and
volunteers, develop a community-based environmental education program, serve as a basis
for the development of research projects and
theses for students and other investigators,
and catalyze other local and regional conservation initiatives. Monitoring programs that
incorporate mist netting can also be used as a
public education tool, teaching schoolchildren
and adults the beauty of birds and the importance of healthy ecosystems.
9
LATTA ET AL.
As is often the case, training is vital to any
avian monitoring effort, and toward this end,
joint efforts of various organizations and individuals are underway to offer training in monitoring methods. Such programs are offered
by PRBO Conservation Science (formerly
Point Reyes Bird Observatory; http://
www.prbo.org), Klamath Bird Observatory
(http://www.klamathbird.org), and the U.S.
Forest Serviceís Redwood Science Laboratory
(http://www.fs.fed.us/psw/rsl/), among others. Monitoring workshops enable individuals
and local conservation organizations to provide biologists, land managers, and naturalists
with the skills necessary to conduct standardized avian monitoring, as well as the analytical
skills necessary to manage and interpret their
data (e.g., Nur et al. 1999). Course participants
are introduced to basic concepts in avian
ecology and conservation biology, as well as
bird identification, census methodologies,
monitoring techniques, and environmental
sampling, all adapted to their specific locales.
These monitoring courses increase the
exchange of information among biologists
and monitoring stations throughout the
Americas. The contacts and partnerships generated through the training courses, and the
establishment of the additional monitoring
programs, greatly enhances communication
among biologists, fosters cooperation, and
increases the effectiveness of larger-scale
monitoring efforts advocated here.
ACKNOWLEDGMENTS
We thank participants of the U.S. National
Park Serviceís and American Airlineís International Workshop for Park Flight Grantees
held in Pico Bonito National Park, Honduras
in November 2002, and the VI Congreso Para
el Estudio y Conservación de las Aves de
México (CECAM) meeting in Culiacán,
Sinaloa, México in March 2004, for their
interest and comments on presentations of
10
earlier versions of this monitoring scheme.
We also acknowledge the generous support of
the Goldman Foundation and an anonymous
donor for their support of PRBO Conservation Scienceís Latin America program. Raymond McNeil and two anonymous referees
helped to improve the manuscript. This is
Contribution Number 1189 of PRBO Conservation Science.
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